"Erat autem miles quidam Rogerus de Coincneriis, vir bonus et fidelis; hic non acquievit communicare actibus Willelmi Cumin. Unde in possessione sua, scilicet in Biscoptun, firmavit sibi munitiunculam, quia locus congruebat circumcinctus palude"
Although this document has been considered by some as a licence to crenellate the current opinion rejects this as a licence to crenellate.
Cited as being licenced, but Conyers was chief supporter of Bishop against usurpation by William Comyn in 1143, so more a fortification by necessity than by consent. King notes the document but did not consider it a licence to crenellate. Not, in a meaningful sense, a licence to crenellate although has been called this by some. Nothing in the relevant sections of Simeon of Durham reads anything like a licence to crenellate, neither the terms 'licence' or 'crenellate' occur.
Original source is
(In fact, the original source given is usually a transcription/translation of what are precious medieval documents not readily availably. It should be noted that these transcription/translations often date to the nineteenth or early twentieth centuries and that unwitting bias of transcribers may affect the translation. Care should also be taken to avoid giving modern meaning to the medieval use of certain stock words and terms.)
Significant later source are;
there is sufficient evidence from charters in the Treasury to prove that the Norman family of Conyers, Lords of Bishopton (and possibly from the same early date owners of Sockburn), held the rank of nobles or Barons of the Bishopric at least from the reign of Henry I. Bishop Ralph Flambard gave Rungetun in Yorkshire to Roger Conyers before 1126. His son was that Roger Conyers whose important services to Bishop William de St. Barbara are on record in Simeon. The story runs thus: Conyers afforded the Bishop a safe retreat in his strength or Peel-house of Bishopton; and he afterwards had the address to bring the Scotch intruder Comyn a humble, kneeling penitent before the Episcopal throne. To bring about this most wished conclusion implies as much courage, and certainly more address, than if the Constable had finished the contest in the usual manner with the bloody hand. The Constable's staff, and the Wardenship of Durham Castle, which he had recovered from Comyn, seems a most appropriate reward; and if the green acres of Sockburn were added to the gift, he was still not overpaid. (Surtees - sourced from The Battle Abbey Roll http://www.1066.co.nz/library/battle_abbey_roll3/subchap186.htm)
Biographical source include;
More details about licences to crenellate can be found here.
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